invoice sent along with e-signature request

I don't use this feature myself (I bill through Ignition, it combos with my EL's, wonderful!), but I do know enough about QB/Intuit Merchant Services to know that IF it's possible, you'd do that through your merchant services login, to not accept credit cards, only ACH.

I'd recommend you test it by sending yourself a dummy 8879 and see what it prompts you for with payment options. As long as you don't actually pay or complete the DocuSign, there will be no fee and you can later void the DocuSign and get the envelope back.

One final thought, if I may. Opinions abound on this, but I take the view to accept credit cards and eat the fee. I'll readily admit my privilege that I can just increase my fees to absorb it. I know not every preparer/locality/practice can, so I say this cautiously and respectfully. The mantra that guides my decision to accept cards and eat the fee is "don't make it hard for your customers to pay you."